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Electronic Tricks & Helpful Hints
Suggestions, Tips & Rules of Thumb for Protoype Breadboards
Last Updated: Saturday, October 04, 2008 03:07 AM

ELECTRONIC BREADBOARDING TECHNIQUES
Breadingboarding Tool List

There are two basic bread boarding methods that I have used over the last 30+ years. One method uses lots of IC sockets that are designed for pin to pin wire-wrapping methods and uses minimal hand soldering. The other method uses pins pushed into a perforated board and requires that every lead of a component be hand soldered to a pin. I suggest that you use wire wrapping methods only when they are justified. Wire wrapping should be considered when the design calls for a large number of logic ICs that can easily be mounted on a perforated board with plenty of room between ICs. Wire wrapping methods should not be used for high frequency, medium power, low level signals or designs that call for a large number of discrete parts.

If the basic circuit design is not clear, I suggest that you first test and refine the circuit using a solderless breadboard system. Such systems allow components to be quickly changed and additions made. A circuit can usually be assembled and tested on a solderless breadboard system in about one tenth the time it would take to hand solder the same circuit. Using the solderless breadboard, you can make sure the circuit functions properly before you solder the parts together on a breadboard.

In either method, I recommended that the circuit be elevated off the table to prevent components and pins on the bottom of the board from touch a metal table top. If you use a wire wrap technique, you will need at least 3/4 inch space under the board. Hand soldered board may be able to safely use 3/8 or � inch spacing. 1/4 inch diameter metal standoffs of appropriate length mounted in each corner of the board is a great way to keep the circuit bottom off of the table.

In hand soldered boards, some care will need to be taken to insure a successful outcome. When there is sufficient board space, layout the resistors and diodes in a horizontal manner. Try to position the circuit components in a neat right angle configuration. Don't put components at funny angles unless you absolutely must. Use easy to solder Vector solder pins whenever possible to allow for component value changes without disturbing the underside wiring. Always use IC sockets.

Never solder the components directly to an IC unless circuit size is a concern. Blown ICs are difficult to remove when there are a dozen parts soldered to them. Always solder the IC socket completely first, then install the ICs into the sockets when the whole circuit is finished. If the ICs are loaded into the socket during the soldering process problems may result. The heat from the soldering iron can cause the ICs to be damaged or to be glued into the sockets.

Do all your soldering on the bottom of the board if possible with all the components on top. Don't zig-zag wires through both sides of the board. It is a lot easier to trace the wiring when all the connections are made on one side, even if many insulated wires cross over each other. Use bare 28ga tin plated wire for most of the low current connections but shift to larger size wires as needed. Some long power and ground wires should be increased to 24ga or 22ga. High temperature insulated 28ga wire ("Tefzel" from Vector) is ideal for connections that must cross over each other. You might find it easier to use some thin Teflon sleeving on some short wires around ICs. 28ga high temperature wire-wrap wire is also good for long connections that have to snake through and over other components. Remember, load the ICs into the sockets after all the wiring is done. White plastic IC pin tags (From OK tool) are great to keep track of the IC pin number when soldering the bottom of the board. If you don't have the tags, circle pin number 1 on the circuit board bottom with a waterproof felt tipped pen. Then, at least you will have some reminder of the IC pin numbers when soldering. Have a copy (not the original) of the schematic close by and mark it with a yellow marker as you wire up the connections. You should also double check each connection after you have finished soldering.